Field of the Invention
Arrangements for such car-parking facilities are described in Swedish Patent Specification No. 8801396-6 corresponding to U.S. Pat. No. 4,986,714, dated Jan. 22, 1991, entitled "Vehicle Elevator and Conveyor Arrangement". In principle, this patent specification teaches a so-called transfer trolley which can be transported horizontally on rails and vertically with the aid of a lift or hoist arrangement. The transfer trolley is movable in these directions within a vertical shaft which is surrounded by parking places on two mutually opposite and parallel sides thereof. Each side includes a number of floors and each floor, or storey, includes a plurality of mutually adjacent parking places.
The transfer trolley includes a first carriage which supports a second carriage. This second carriage is fixedly connected to the first carriage but movable in relation thereto in the direction of its longitudinal axis. A car in a transport position is raised on the second carriage. The longitudinal axes of the carriages, similar to the longitudinal axis of the car, extend perpendicularly to the longitudinal axis of the shaft.
In brief, the described arrangement functions in the following manner: A car is driven onto the transfer trolley on the bottom floor of the complex, whereafter the trolley is transported horizontally and/or vertically to a position in front of a vacant parking space. The second carriage is then displaced in the direction of its longitudinal axis relative to the first carriage into the parking space, where the second carriage deposits the car. The second carriage is then moved back in over the first carriage, whereafter the whole of the transfer trolley is moved to some other location within the building, in readiness for transporting cars in or out.
When a car is to be transported out, the transfer trolley is moved to the parking place concerned, whereafter the second carriage is moved in beneath the car, and lifts the car and moves the same back in over the first carriage, whereafter the transfer trolley is moved to a delivery station on the bottom floor of the car-parking building.
It will be obvious from this that it must be possible to move the second carriage in relation to the first carriage to an extent in which a car located on the first carriage can be deposited in a parking space at a distance from said carriage which extends so far into said space that the car is completely free from the transfer trolley when said second carriage is drawn-in over the first carriage, subsequent to having deposited the car. In this latter state, the transfer trolley has a length which corresponds to the width of the shaft. Consequently, in order to be positioned so that it is located substantially completely in a parking space, it is necessary to be able to displace the second carriage relative to the first carriage to an extent such as to locate the second carriage essentially completely outside the confines or outer extensions of the first carriage, or in a position edge-to-edge with said first carriage. The need for this extensive carriage displacement is complicated by the fact that the only available length for the carriage-displacement mechanism is the length of the transfer trolley, which corresponds to the width of the shaft.
This problem is solved in a highly advantageous manner by means of the present invention, where the length of the drive device or carriage displacement mechanism is much shorter than the length of the transfer trolley.